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    <p>This text contains subscript</p>
    <p>The chemical formula of water: H2O</p>

    <p>This text contains <sub>subscript</sub></p>
    <p>The chemical formula of water: H<sub>2</sub>O</p>
    <p>The chemical formula of water: H<span style="vertical-align: sub ; font-size: small">2</span>O</p>

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